This invention relates to an emergency descent device and particularly to one having a fluid rotation-retarding device for controlling the rate of the descent.
Emergency descent devices having a rotating spool with a cable wound thereon and a fluid rotation-retarding means are known in prior arts. U.S. Pat. Nos. 4,018,423, 3,847,377 and 3,946,989 discloses descent devices having fluid rotation-retarding units which include one or more vane members deviding a fluid-filled, sealed housing into two or more volume variable chambers which are then communicated by providing one or more passages. These passages are adjustable to control the rotating rate of the vane. However, the adjustment of the passage is usually done manually.